The present invention generally relates to the field of information handling system, and particularly to a method and system for peripheral ordering.
Operating system architectures typically require the use of a boot and system disk drive to store files needed during initialization. The boot and system drives are identified by the operating system by the respective order in a list of peripherals available. Typically, the boot drive is the first drive and the system drive may be any other drive but must maintain its order in the list. The list of available peripherals is created by and provided to the operating system by the I/O interface controller. The I/O interface controller must make sure the boot and system drive remains in the same location in the list.
Typically, I/O architectures allow a user to assign a specific identification number to a peripheral. Thus, it is up to the user to make sure that the list of available peripherals is ordered correctly based on the specific I/O interface controller used and the order of IDs assigned. For example, a small computer system interface (SCSI) controller orders its peripherals from lowest to highest based on the SCSI ID. Thus, it is the responsibility of the user to make sure that the boot and system drive ID remains constant. In another example, a fibre channel (FC) controller orders its peripherals from lowest to highest based on the arbitrated loop peripheral address (ALPA) automatically assigned to each peripheral during loop initialization. Therefore, it is again the user""s responsibility to make sure that the boot and system drive remains in the same location in the list of available peripherals. Since these ID""s are assigned automatically by the hardware loop initialization the user has no way of maintaining the ordering of the peripherals.
Additionally, the lack of the ability to retain peripheral ordering has limited the advancement of ID assignment. For example, SCSI configured auto-magically (SCAM) is a method to allow SCSI peripherals to be identified automatically. Although this ID assignment method did assign ID""s automatically it was not accepted in the industry because there was no available method for constant ordering of the peripherals when a new device was added. Thus, SCAM was not accepted as a valid method for automatic ID assignment for SCSI.
Thus, it would be desirable to provide a system and method of retaining peripheral ordering.
Accordingly, the present invention is directed to a system and method of retaining peripheral ordering. In a first aspect of the present invention, a method for retaining peripheral ordering in an information handling system includes reading an ordered peripheral list (OPL) from a nonvolatile memory. A list of active peripherals attached to an I/O interface controller is obtained. An order of peripherals from the ordered peripheral list (OPL) is identified and assignments are assigned to the active peripherals attached to the I/O interface controller corresponding to the ordered peripheral list (OPL).
In a second aspect of the present invention, a device suitable for retaining peripheral ordering includes an I/O interface controller suitable for controlling an I/O interface and a nonvolatile memory including an ordered peripheral list. The ordered peripheral list is suitable for supplying an order of peripherals to an I/O interface controller such that active peripherals that are identified are capable of receiving an assignment corresponding to the ordered peripheral list (OPL), thus allowing at least one of a system drive and boot drive to remain in a specific place in the list of active peripherals upon rebooting.
In a third aspect of the present invention, a method for retaining peripheral ordering in an information handling system includes booting an information handling system and executing a basic input/output system (BIOS) included on the information handling system. An ordered peripheral list (OPL) stored in a nonvolatile memory is read by the BIOS and a list of active peripherals coupled to an I/O interface controller is obtained. An order of peripherals is identified wherein the list of active peripherals is compared to the ordered peripheral list (OPL). Assignments are given to the active peripherals corresponding to the ordered peripheral list (OPL).
It is to be understood that both the forgoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention as claimed. The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate an embodiment of the invention and together with the general description, serve to explain the principles of the invention.